Machine for applying a coating to the inner side of caps and the like dished objects



y 0, 1967 P. GELBJERG-HANSEN ETAL 3,322,095 MACHINE FOR APPLYING A COATING TO THE INNER SIDE OF CAPS AND THE LIKE DISHED OBJECTS Filed Dec. 4, 1962 4 Sheets-Sheet l INVENTURfi! z!- Q/W- azure; Bynnl jg, v

76 A TTORNEX May 30, 1967 P. GELBJERG-HANSEN ETAL MACHINE FOR APPLYING A COATING TO THE INNER SIDE Filed Dec. 4, 1962 OF CAPS AND THE LIKE DISHED OBJECTS 4 Sheets-Sheet 2 i -14 IV I K INVENT fir 'I /MJQ BY M 4 'w WE/IQ ATTORNEY.

y 0, 1967 P. GELBJERG-HANSEN ETAL 3,322,095

MACHINE FOR APPLYING A COATING TO THE INNER SIDE OF CAPS AND THE LIKE DISHED OBJECTS Filed Dec. 4, 1962 4 Sheets-Sheet By W 90 fgend fi LBJERG-HANSEN ETAL 3,322,095 FLYING A COATING TO THE INNER SIDE AND THE LIKE DISHED May 30, 1967 P. GE MACHINE FOR AP 0F CAPS Filed Dec. 4, 1962 OBJECTS Sheets-Sheet 4 2w 114 BYM & ,y. M N m a; .1 N? T United States Patent 3,322,095 MACHINE FOR APPLYENG A COATING TO Tim INNER SIDE OF CAPS AND THE LIKE DISHED OBJECTS Per Gelbjerg-Hansen, Copenhagen, and Hoiger Meyendorfi, Lyngfy, Denmark, assignors to F.G.M. & (30., Copenhagen, Denmark, a Danish firm Filed Dec. 4, 1962, Ser. No. 242,117 Claims priority, application Denmark, Dec. 4, 1961, 4,830/61 17 Claims. (Cl. 118-2) The present invention relates to machines for applying a coating to the inner side of caps and the like dished objects which are rotated during the introduction of a liquid coating composition, for example a solution or melt or" a coating composition, into the objects so that said coating composition is by centrifugal forces distributed over the portions to be coated.

More particularly the invention relates to such machines for applying a thin, preferably film-like coating on the inner side of the skirt portion of plastic bottle caps provided with a bottom, a skirt portion and a head at the free edge of said skirt portion.

It is known to provide lids or the like covers made from metal or plastic for closing tins, glass, jars or other containers, with a sealing layer along the edge of the bottom of the lid, at and in the transition between the latter and the skirt portion of the lid, and it is also known to apply these coatings by dripping a certain amount of coating composition into the lid while the latter is rotating so that the coating composition is distributed along the edge of the bottom owing to the influence of the centrifugal forces.

The known machines for application of a coating composition in this manner are provided with a number of continuously rotating dished lid receiving members, to which the lids are fed by means of a discontinuously moved conveyor belt, each lid being when positioned over a receiving member forced down into the latter by means of a movably and rotatably mounted piston. Thereafter the necessary quantity of coating composition is dripped into the rotating lid, whereafter by means of an ejector rod the latter is pushed out of the receiving member for reengagement with the conveyor belt by which thereupon it is transferred to a hardening plant.

However, such a machine is not quite suitable when a film of coating composition is to be applied to the inner side of the side wall or skirt portion of a bottle cap. This is inter alia due to the fact that as a rule bottle caps have a relatively small diameter so that in order to obtain the necessary centrifugal action for producing an equal distribution of the coating composition on the inner side of the skirt portion it is necessary to use an essentially greater rotary speed of the receiving members than the one used in the hitherto known machines, which further involves that the caps cannot with sufiicient effectiveness be brought into and out of engagement with the rotating receiving members. Consequently the latter would have to be driven discontinuously whereby the capacity of the machine would be further reduced. Another difiiculty is that for obtaining an even distribution of the coating composition on the inner side of the skirt portion of a cap it is necessary or at any rate advantageous that the cap should be obliquely arranged during the rotation which by the known machines would render the transfer of the caps from the conveyor belt to the receiving member and back to the conveyor belt difiicult.

An object of the invention is to provide a simple, effective and comparatively inexpensive machine of the kind stated above.

Another object of the invention is to provide a machine of the kind stated above which despite a great capacity 3,322,095 Patented May 30, 1967 renders it possible to obtain a secure feeding and removal of the caps to and from the receiving members while the rotation of the latter is stopped, and a very quick rotation of the receiving members with the caps or similar objects during the application of the coating composition and immediately thereafter.

A further object of the invention is to provide a machine of the above stated kind, in which the feeding of the caps to the receiving members, the introduction of coating composition into the caps, and the removing or ejection of the caps from the receiving members are carried out at three different stations so that said three op erations cannot interfere with each other.

A still further object of the invention is to provide a machine of the kind stated above that has a series of receiving members and in which for each receiving member the three main operations, cap feeding, dripping of the coating composition into the cap during rotation thereof, and cap ejection, take place completely independent of each other and at different positions, which besides a satisfactory carrying out of each of said operations also renders a great capacity possible, and in which the caps may during the dripping of the coating composition into the caps be given any desired oblique position without this having any influence upon the reliable performance of the two other operations.

Still another object of the invention is to provide a machine of the kind stated in which an exact measured quantity of the coating composition is dripped into each cap during rotation thereof.

Still another object of the invention is to provide a machine of the kind stated above in which the carrying member for the receiving members, constituted by a rotatable drum, always travels in the same direction without reciprocation, so that simple driving means for said carrying member may be used and that compared with its capacity the machine only occupies a comparatively small space.

Further objects and advantages of the present invention will become apparent from this specification, claims and accompanying drawings, which schematically show a preferred embodiment of the invention and wherein:

FIG. 1 is a cross section through a drum, forming a part of the machine, and the most essential devices cooperating therewith,

FIG. 2 is a rear elevational view on a minor scale of the machine with portions of a rear covering plate broken away,

FIG. 3 is a cross-sectional view along line IIIIII in FIG. 2 showing one end of the drum and a driving device therefore,

FIG. 4 is a plan view of a portion of the drum with portions in section,

FIG. 5 is a cross sectional view of the other end of the drum showing a driving device for rotation of a row of cap receiving members disposed in the drum, further corresponding driving devices being removed for the sake of clarity, and

FIG. 6 is a sectional view along the line V'.[VI in FIG. 5.

The machine illustrated is provided with two side frame members 19 and 12, see FIG. 2, between which extends a stationary shaft 14 secured to said frame members. A hollow drum 16 having a drum wall 17 is by means of two transverse walls 15, of which only one is shown, rotatably mounted on the shaft 14.

The drum 16 is adapted to be periodically rotated through an angle of 45 at a time. For this purpose a Geneva movement shown in FIGS. 2 and 3 is used.

On the side of the drum 16 facing the side frame member 10 a disc 18 is arranged coaxial with the drum 16 and secured thereto. The disc 18 is provided with eight equally spaced slots 20 extending radially inwards from the periphery of the disc 18, and between the slots 20 with recesses 22 shaped as circular arcs. On a shaft 24 rotatably mounted in the frame member there is secured a carrier member 26 provided with an arm 28 carrying a rotatably mounted roller 30. When the carrier member 26 is turned in the direction of rotation of the arrow 32 in FIG. 3, the roller 30 will engage one of the slots 20 of the disc 18 whereby during its movement into and out of the slot it will rotate the disc 18 and thereby the drum 16 through an angle of 45 in the direction of rotation shown by an arrow 33 in FIG. 3. The carrier member 26 is furthermore provided with an arched projection 34, which engages,'when the roller 30 moves out of one of the slots 20, the arched recess 22 following after the said slot 20 in the direction of rotation of the disc 18 so that the disc 18 and thereby the drum 16 is maintained stopped during the time the roller 30 is out of engagement with the disc.

The shaft 24 is driven through a variable gear device 36, not shown in detail, from a driving shaft 38 rotatably mounted in the frame members 10 and 12 and in turn driven from an electric motor 40.

The drum wall 17 is provided with eight rows of cylindrical holes 42, which rows have a centre angular distance of 45. Each row comprises eight holes 42 so ar ranged that each hole in a row corresponds to a hole in each of the other rows, and all last said corresponding holes 42 have their axes disposed in the same radial plane of the drum 16.

In each hole 42 there is inserted a cylindrical bushing 44 provided outside the drum with an oblong flange 46, see FIG. 4, secured to the outer side of the drum 16 by means of bolts 48. In each bushing 44 there is by means of ball bearings 47 rotatably mounted a hollow shaft 50 having a portion extending outside the flange 46. On said extending portion there is exchangeably clamped a cap receiving member 52 having at its outer end a dished recess 54, the inner diameter of which is slightly smaller than the outer diameter of the side wall of a cap 56 to be located in the cap receiving member 52. Below the dished recess 54 the receiving member 52 comprises a cylindrical portion 58 provided with a circumferential cord groove 60. If desired, the side wall of the dished recess 54 may be slotted and thereby resilient.

Each receiving member 52 is provided with an axial through bore 62 by which the receiving member is clamped to the corresponding hollow shaft 50 which,

however, does not extend right up to the bottom of the dished recess 54.

In each hollow shaft 50 an ejector pin 64 is slidably mounted. This pin 64 is at its outer end provided with a disc-shaped head 66 the diameter of which is only slightly smaller than the diameter of the bore 62. The inner end of the ejector pin 64 extending inwardly from the hollow shaft 50 has a bump head 68 which is domed at the side thereof facing away from the ejector pin. A pressure spring 70 inserted between the bump head 68 and the inner end of the hollow shaft 50 serves to ensure that normally the head 66 engages the outer end of the hollow shaft 50 and thereby is positioned in the space between said outer end of the shaft 50 and the bottom 55 of the dished recess 54 of the receiving member 52.

At the end of the drum 16 nearest the frame member 12 the drum wall 17 is provided for each row of holes 42 with a further hole 72, see FIG. 5, the axis of which, however, is somewhat displaced in the peripheral direction relative to the axes of the holes 42 in the row. Also in each hole 72 a bushing 74 (only one of which is shown in FIG. 5) is fitted having a fixing flange 76. In this bushing there is by means of ball bearings 78 rotatably mounted a shaft 80 which outside the bushing 74 carries a driving cord pulley 82.

An endless driving cord 84, FIG. 4, passes round the portion of the cord pulley 82 nearest the frame part 12 the row the driving cord is passed back to the cord pulley 82. The returning part of the driving cord 84 is, as appears from FIG. 4, out of engagement with the cylinder portions 58 which is due to the above mentioned arrangement of the hole 72.

The bushing 74 is provided at its inner end with a hollow pin-shaped portion 86. An arm 88 pivoted on this portion 86, FIG. 6, carries at the end thereof nearest the end of the drum 16 an inwardly projecting pin 90 on which a friction wheel 92 is rotatably mounted meshing with another friction wheel 94 secured to the inner end of the shaft 80.

A guide roller 96 is rotatably mounted on the opposite end of the arm 88. A disc 98 secured to the shaft 14 is arranged Within the cavity of the drum 16 at the side of the arms 88 facing away from the frame part 12. The disc 98 is provided at the side facing the arm 88 with an arc-shaped guide or cam 100 extending towards the arm. The roller 96 is adapted to engage the cam 100 for which purpose the arm 88 is by means of a tension spring 102 constantly urged in anti-clockwise direction, see FIG. 6.

As appears from FIG. 2,'a friction disc 104 is rotatably mounted on the shaft 14 immediately outside the drum 16 at the end of the latter facing the frame member. The friction disc 104 is provided with a hub 108 on which a V-belt pulley 110 is secured. The latter and thereby the friction disc 104 are driven by means of a V-belt 112 from a V-belt pulley 114 on the driving shaft 38.

As long as the roller 96 of the arm 88 is out of engagement with the guide or cam 100 the friction wheel 92 by means of the spring 102 is kept in engagement with the friction disc 104 so that the friction wheel 92 is driven and in turn drives the friction wheel 94 which drives the cord pulley 82. This again, by means of the driving cord 84, drives the receiving members 52 of, the corresponding row of receiving members 52 at a rotary speed which owing to the illustrated gearing conditions is very great;

If, however, the drum is turned to a position at which the roller 96 of the arm 88 engages the guide or cam 100, the arm 88 will be swung somewhat in clockwise direction, FIG. 6, whereby the friction wheel 92 is disengaged from the friction disc 104 and the rotation of the corresponding receiving members 52' is stopped.

In the embodiment shown the guide 100 has such a length and is so arranged, see FIG. 5, that the guide roller 96 belonging to a row of receiving members 52 will move away from the guide 100, and the receiving members thus start to rotate at a position of the drum at which the axes of the receiving members 52 of the row point approximately vertically upwards and said receiving members will continue to rotate during the further rotation of the drum 16 in the direction of rotation shown by an arrow 116 in FIG. 5, until the drum has been rotated through slightly more than 90, whereafter the guide roller 96 will again move into engagement with the guide or cam 100, and the rotation will be stopped.

The above mentioned driving device 1830 is so arranged relative to the drum '16 that in any stationary position of the drum 16 a row of receiving members 52 will be so disposed that the axes of the receiving members extend verticallyupwards, whereas the axes of the remaining rows extend radially outwards at a relative angular distance of 45. I

Opposite the row of receiving members 52 which at any stationary position of the drum 16 have their axes pointing obliquely upwards and backwards, i.e. to the right hand side in FIG. 1, and thereby takes up its cap receiving position, there is in the machine stationarily arranged a cap feeding device, as a whole referred to as 118, for each receiving member 52 in the row. In the illustrated embodiment thus eight such devices are arranged.

Each cap feeding device 118 cooperates with a cap supply channel 120 through which the caps 56 can be fed to the device 118. The channels 120 are aggregated in a panel 122 attached to the machine frame above the drum, see FIG. 2, and provided in a manner not shown at the top with an obliquely extending distributing channel taking care thereof that caps 56 moved to the panel are distributed among the channels so that when the machine is running and when the required number of caps is present all said channels will be almost completely filled with caps 56. These caps in turn are supplied from a cap feeder known per se, but not shown, preferably a cap feeder of the drum type, ensuring that the caps are always guided into the panel 122 and consequently to each of the channels 120 oriented in such a manner that their open side at the lowermost end of the latter channels 120 are disposed opposite a receiving member 52 facing away therefrom.

The lower portion of each channel 120 extends parallel to the upper side of the receiving member 52 in its cap receiving position disposed opposite the end of the channel. The wall 124 of the channel 120 facing the receiving member is provided with an opening 126 co-axial with the receiving member 52 and having a diameter slightly larger than the diameter of the outer bead 128 of a cap 56. The channel 120 is at its lower end closed by a transverse wall 130 ensuring that the caps 56 do not move past the opening 126. For preventing the caps from without outer influence falling through the opening 126 the outer side of the channel 120 is provided with leaf springs 132 and 134 the free ends of which extend a little beyond the edge of the opening 126.

The opposite wall 136 of the channel 120 is provided with an opening 138 co-axial with the opening 126, but having a somewhat smaller diameter than the latter. Opposite said opening 138 and co-axial with the receiving member 52 a pneumatic piston device is arranged com prising a piston 142 reciprocably in a cylinder 140 and adapted for movement towards the receiving member 52.

' The piston 142 is in known manner kept withdrawn into the cylinder 140 by means of a spring, not shown, arranged within the cylinder.

The pneumatic piston devices are arranged in an angle iron 144 extending between and attached to the frame members and 12.

Each piston device 140 has in the vicinity of the outwardly facing end of the cylinder a supply pipe 146 for compressed air which as will be described hereinafter can be admitted through an air supply pipe 148 common to the tubes 146 of all the piston devices 140, 142.

If compressed air is admitted to the cylinder 140 the piston 142 will move towards the channel 120 and through the opening 138 of the latter for engagement with the bottom of the cap 56 located inside the same. The piston 142 will thereafter carry along the cap 56 and overcoming the resistance of the springs 134 and 136 move the cap out of the channel 120 towards the cap receiving member 52 whereafter the side wall of the cap extending from the bead 128 thereof to the cap bottom will be forced into the dished portion 54 of the receiving member 52 and be clamped in the latter. When later on the air pressure ceases and the space within the cylinder 140 above the piston 142 is connected to the atmosphere, the piston 142 will return to its start position outside the channel 120 so that a fresh cap 56 can move into position opposite the openings 126 and 138.

When caps 56 have been located in a row of receiving members 52, the drum 16 is turned forward twice in the direction of rotation shown by an arrow 116 in FIGS. 1 and 5, until a stationary drum position at which the axes of the row of receiving members in question extend obliquely upwards and forwards. At this coating composition dripping position a certain amount of liquid coating material, such as an ammoniacal latex solutionis fed or dripped into each cap' 56.

For this purpose for each of the receiving members 52 in the row a coating material dripping device, as a whole indicated by 150, is arranged. Each such device comprises a stationary outlet pipe 152 supported by a supporting member 154 secured to a transverse rod 156 extending between and fixed to the frame members 10 and 12. The pipe 152 is so arranged that in consequence of the oblique position of the receiving members 52 a drop coming from the pipe will fall down into the interior of the cap 56 located under the pipe at the downwardly facing transition between the bottom and side wall of the cap. As mentioned above, in the said position the receiving member 52 is rotated at a very high speed of rotation whereby the admitted amount of coating material will by the centrifugal force be evenly distributed practically solely over the inner side of the side wall of the cap within the bead portion 128 thereof.

However, the admitted amount of coating material must be dosed very exactly, and for this purpose an electromagnetic valve is provided indicated as a whole by 158.

The fluid coating material is supplied from a container, not shown, which may, if desired, be at a pressure above that of the atmosphere, and is fed to the outlet pipe 152 through a fluid pipe 160. The latter communicates with the outlet pipe 152 through a short compressible hose 162 abutting the transverse rod 156. On the side of the hose 162 opposite the latter a pressure member 164 is arranged mounted at the end of a rod 165 which is connected to the armature, not shown, of an electromagnet 166 supported by a bracket 168 secured to the transverse rod 156 and having a front plate 170 facing the transverse rod 156. Between said front plate 176 and the pressure member 164 a pressure spring 172 is inserted enclosing the rod 165. When the electromagnet 166 is in its neutral state, the spring 172 will force the pressure member 164 towards the transverse rod 156 and thereby compress the hose 162 so that the liquid flow through the hose is cut off. If, on the other hand, the electromagnet 166 is energized, the pressure member 164 will be drawn away from the hose 162 and thus open for the passage of the fluid. In this manner an extremely simple, but very quickly acting valve is obtained.

The circuit, not shown, of the electromagnet 166 includes a not shown adjustable electric time relay of a type which when energized ensures current supply to the electromagnet 166 for a period depending only on the setting of the time relay, but being independent of the duration of the energizing current. Such a time relay works as to time with very great accuracy and will therefore in cooperation with the above further described very quickly working electromagnetic valve 158 ensure an extremely exact closing of the amount of coating material supplied to each cap.

The actuating circuit for the above mentioned time relay includes a breaker 174, 176 comprising a fixed contact 174 and a movable contact 176. The latter is connected to a lever 178 pivoted on a stationary shaft and serving as a feeler.

The feeler 178 is so arranged that it engages the outwardly facing portion of the receiving members 52 which during the rotation of the drum 16 move up beneath the feeler. It is furthermore so arranged that the swinging movement which it is given in clockwise direction, FIG. 1, by engagement with a receiving member 52 in which there is no cap 56, is too small for closing the breaker 174, 176 and thereby for cutting in the actuating current for the corresponding time relay. For this purpose it is required that the feeler engages a cap 56 located in the receiving member '52, which cap 56, in consequence thereof that a portion of the cap projects outside the receiving member 52, will give the feeler 178 a greater swinging movement so that the contact closing between the contacts 176 and 174 can be ensured. By this arrangement it is obtained that the electromagne't 166 is energized only when a cap 56 is situated under the corresponding outlet-pipe 152 thus preventing a dirtying of the receiving member 52 with coating means, when for example in the event of erroneous functioning there is no cap in the receiving member. Moreover, it is ensured that the coating means is introduced into the cap 56 at the same time as the drum 16 is brought to a standstill after the receiving member 52 has been brought to the position where the coating material has to be applied so that the time of rotation of the cap after the application of the coating material is of the longest possible duration.

Within the drum 16 two pneumatic piston devices 182, 184, of which only one is shown on the drawing, are arranged on the shaft 14. These piston devices are so arranged that their axes extend radially vertically downwards. The two pistons 184 of the piston devices, which in a manner not shown are normally by means .of springs forced as far as possible into the cylinders 182 of the devices, are interconnected by means of an ejector beam 186 extending in the axial direction of the drum 16 over the greater part of the length thereof.

When at a stationary position of the drum a row of receiving members takes up its cap ejection position in which the axes of its receiving members extend vertically downwards the bump heads 68 on the ejector pins 64 of this row will be disposed opposite the ejector beam 186 as appears from FIG. 1.

The innermost ends of the cylinders of each of the pneumatic piston devices communicate through channels (not shown) in the shaft 14 with an axially extending bore or channel 188 formed in the same, said channel 188 being closed at the end of the shaft 14 adjacent the frame part 10, but open at the opposite end of the shaft and tightly fitting connected to 'an air supply pipe 190, see FIG. 2, to which compressed air can be conducted, as will hereinafter be described. If compressed air is conducted into the channel 188 and consequently into the pneumatic piston devices 182, the pistons 184 will be moved outwards and thus force the ejector beam 184 in the outward direction. The latter will thereby engage the bump heads 68 disposed opposite the same and thereby force the ejector pins 64 outwards through the hollow shafts 50. Hereby the heads 66 of the ejector pins 64 will engage the caps 56 located in the corresponding receiving members 52, and thus eject the caps from the receiving members. From the latter the caps will fall down upon a perforated band conveyor 192 by which they can be carried to a not further described drying channel to produce a complete hardening of the coating material introduced into the caps.

As described above, the receiving members 52 have ceased to rotate when they are in their position opposite the ejector beam 184, and so the treated caps can comparatively quietly fall down on the band conveyor 192 with a regular distribution on the same.

It should be observed that the ejector pins 64 may be omitted and the ejector beam 186 instead be provided with ejector pins which during the outward movement of the beam are moved into the hollow shafts 50 'for engagement with and ejecting of the caps 56. Such a construction will, however, as a rule be less advantageous among others while it requires a very long movement of the pistons 184 as well as special guide members to ensure correct engagement between the ejector pins and the hollow shafts 50. V

The control of the supply of compressed air to the pneumatic piston devices 140, 142 and 182, 184 may advantageously be derived from the shaft 24 since this shaft undertakes one revolution for each travelling of the drum 16. It is for example possible to use a control device 194 of the type shown in FIG. 3, which control device is for the sake of clarity not shown in FIG. 2.

The control device 194 comprises a cylindrical slide box 196 closed at the one end and wherein a slide 198 having two lands 200 and 202 and between them a narrowed portion 204 is slidably arranged. The slide box 196 is provided with three gates 206, 208 and 210, of which the gate 206 nearestthe open end of the slide box 196 communicates with the open air, while the gate 208 located nearest the closed end of the slide box 196 by means of a pipe 212 is connected to a compressed air source (not shown). The third gate 210 is located practically halfway between the two other gates and is by means of a pipe 214 connected to a distribution box 216 from which two pipes 218and 220 are branched off, one of which is in a manner not shown connected to the air supply pipe 148 of'the cap feeding devices 118, while the other, likewise in a manner not shown, is connnected to the air supply pipe communicating with the channel 188 in the shaft 14 and thus with the piston devices 182, 184. V

The slidej198 is provided with a forwardly projecting pin 222 which by means of a connecting link 224 is connected to an arm 228 pivoted on a stationary pin 226. The longitudinal edge 230 of the arm 228 facing away from the slide 214 is situated in the path of movevent of the roller 30 of the Geneva-gear-device and in such a manner that immediately after the roller 30 has moved out of a groove 20 in the disc 18, and thus immediately after the drum 16 has been stopped after a travelling movement, the roller 30 will engage the arm edge 230 whereby the arm 228 is swung in clockwise direction, FIG. 3, and the slide 198 is displaced to the left in FIG. 3, from its normal position shown, in which 7 it establishes communication between the gate 210 connected to the piston devices 140, 142 and 182, 184, and the gate 206 communicating with the open air, to its opposite position in which it establishes communication between the gates 208 and 210 so that compressed air is conducted to the piston devices 140, 142 and 182, 184.

Thus immediately after each travelling of the drum the position where it establishes communication between. the gates 208 and 210 is for some time retained in this position until the roller 30 moves away from the arm 228. Thereafter a pressure spring 232 inserted between the inner end of the slide 198 and the bottom of the box 196 will press the slide 198 back to its above mentioned normal position so that the piston devices 140, 142 and 182, 184 communicate with the atmosphere and their pistons 142 and 184 will return to their start positions.

The above described and partly diagrammatically shown embodiment of a machine according to the invention is only to be considered as an illustration and not in a limiting sense, and it may be modified in many respects without departing from the scope and spirit of the invention. For example,instead of eight rows of receiving members 52 in the drum 16, it is possible to have both more or less rows, however, at least three rows. The use of eight rows has, however, proved most advantageous since by this arrangement it becomes possible to obtain a suitable distance between the cap feeding device 118, the dripping devices 158 for the coating materiaLand the ejection devices 182-186, as well as such an arrangement of said devices relative to the drum 16 that each of them will get the best possible conditions for their operation.

The said devices may, however, also be arranged in other manners. If for instance the machine, instead of for caps of the above described type, is intended to be used for lids to be provided with a coating on the entire lid bottom, the dripping devices for the coating material may be so arranged that the coating material is applied at the middle of the lid located in a receiving member 52 having its axis extending vertically upwards. In certain cases it may also be advantageous that the ejecting device 182484 is so arranged that it cooperates with receiving members 52, the axes of which extend obliquely forwards and downwards or even obliquely backwards and downwards. Y

It should also be observed that instead of pneumatic control and driving of the cap feeding devices and the cap ejecting devices, it is also possible to use for example hydraulic or electric control and/ or driving of these devices, which may also be controlled and/or driven mechanically. The dripping device for the coating material may instead of by means of the shown feeler be actuated in other manners, for example from the shaft 24, and the illustrated electromagnetic valves may be replaced by other types of electromagnetic valves or by pneumatically, hydraulically or mechanically operated valves.

We claim:

1. A machine for applying a coating to the inner side of caps and the like dished objects which are rotated during the introduction of a liquid coating composition into said objects so that said coating composition is by centrifugal forces distributed over the portions to be coated of said inner surfaces of said objects; comprising in combination; a machine frame; a drum rotatably mounted in said frame; a drum driving device connected to said drum for periodical rotation thereof through an angle of not more than 120 a time between at least three stopped positions of said drum; at least three rows of cap receiving members on said drum, each said row extending in the axial direction of said drum, each said receiving member being rotatably mounted on said drum and being provided with an outwardly open dished portion for receiving one of said objects, each of said rows taking up at one of said stopped positions of said drum, a cap receiving position, at another of said stopped positions of said drum a coating composition dripping position, and at a third of said stopped drum positions of said drum a cap ejection position, said cap receiving position being the same for all said three rows, said dripping position being the same for all said three rows, and said cap ejection position being the same for all said three rows; a series of cap feeding devices stationarily arranged in said frame outside said drum opposite said cap receiving position of said rows and adapted each time one of said three rows occupies the said cap receiving position to force one of said objects into each of said receiving members of last said row; a series of coating composition dripping devices stationarily arranged in said frame outside said drum opposite said dripping position of said rows and adapt-ed each time one of said three rows occupies the said dripping position to drip a portion of said coating composition into such of said objects which are carried by the said receiving members of the last said row; ejection means arranged in said frame opposite said ejection position of said rows; actuating means connected to said ejection means for actuating the same to eject when one of said rows occupies the said cap ejection position from said cap receiving members of last said row such of said objects which are carried by last said receiving members; for each said row a cap driving device arranged on said drum and adapted to rotate said receiving members of the corresponding one of said rows; rotation control means cooperating with said cap driving devices and adapted to actuate each said cap driving device before the corresponding one of said three rows during said periodical driving of said drum arrives at said dripping position and said cap driving device to remain actuated until last said row has been moved away from said dripping position, and to inactivate each said cap driving device before the corresponding one of said three rows arrives to said cap extraction position.

2. A machine as defined in claim 1; said cap driving device comprising; a cord pulley connected to each of said receiving members of the corresponding one of said three rows, a cord driving wheel rotatably mounted on said drum; said receiving members of last said row having their axes of rotation disposed in the same plane; said cord driving wheel having its axis of rotation disposed outside said plane; an endless driving cord, passed from said cord driving wheel in a zigzag path between said cord pulleys engaging the same and from the said cord pulley of the corresponding said row remotest from said cord driving wheel back to the latter without engagement with said cord pulleys.

3. A machine for applying a coating to the inner side of caps and the like dished objects which are rotated during the introduction of a liquid coating composition into said objects so that said coating composition is by centrifugal forces distributed over the portions to be coated of said inner surfaces of said objects; comprising in combination a machine frame; a drum rotatably mounted in said frame; a drum driving device connected to said drum for periodical rotation thereof through an angle of not more than a time between at least three stopped positions of said drum; at least three rows of cap receiving members on said drum, each said row extending in the axial direction of said drum, each said receiving member being rotatably mounted on said drum and being provided with an outwardly open dished portion for receiving one of said objects, each of said rows taking up at one of said stopped positions of said drum a cap receiving position, at another of said stopped positions of said drum a coating composition dripping position, and at a third of said stopped drum positions of said drum a cap ejection position, said cap receiving position being the same for all said three rows, said dripping position being the same for all said three rows, and said cap ejection position being the same for all said three rows; a series of cap feeding devices stationarily arranged in said frame outside said drum opposite said cap receiving position of said rows and adapted each time one of said three rows occupies the said cap receiving position to force oneof said objects into each of said receiving members of last said row; a series of coating composition dripping devices stationarily arranged in said frame outside said drum opposite said dripping position of said rows and adapted each time one of said three rows occupies the said dripping position to drip a portion of said coating composition into such of said objects which are carried by the said receiving members of the last said row; ejection means arranged in said frame opposite said ejection position of said rows; actuating means connected to said ejection means for actuating the same to eject when one of said rows occupies the said cap ejection position from said cap receiving members of last said row such of said objects which are carried by last said receiving members; for each said row a cap driving device arranged on said drum and adapted to rotate said receiving members of the corresponding one of said rows; rotation control means cooperating with said cap driving devices and adapted to actuate each said cap driving device when the corresponding one of said rows occupies its said dripping position, and to inactivate each said cap driving device at least when the corresponding one of said three rows occupies its said cap receiving position and when last said row occupies its said cap extraction position; each said cap driving device comprising; a first driving wheel rotatably mounted on said. drum and being in driving connection with said receiving members of the corresponding one of said rows; an arm pivoted to said drum; the pivot axis of said arm being coaxial to said cap driving wheel; a driver wheel rotatably mounted on said arm excentrically to said pivot axis and being in driving connection with said first driving wheel; a driving ring rotatably mounted said objects so that said coating composition is by cen-t trifugal forces distributed over the portions to be covered of said inner surface of said objects, comprising in combination; a machine frame; a drum rotatably mounted in said frame; a drum driving device connected to said drum 7 for periodical rotation thereof through an angle of not more than 120 a time between at least three stopped positions of said drum; at least three rows of cap receiving members on said drum, each said row extending in the axial direction of said drum, each said receiving member being rotatably mounted on said drum and being provided with an outwardly open dished portion for receiving one of said objects; each of said rows taking up at one of said stopped positions of said drum a cap receiving position, at another of said stopped positions of said drum a coating composition dripping position, and at a third of said stopped positions of said drum a cap ejecting position, said cap receiving position "being the same for all three said rows, said dripping position being the same for all said three rows, and said cap ejection position being the same for all said three rows; a series of cap feeding devices stationarily arranged in said frame outside said drum opposite said cap receiving position of said rows and adapted each time one of said three rows occupies its said cap receiving position to force one of said objects into each of said receiving members of the last said row; a series of coating composition dripping devices stationarily arranged in said frame outside said drum opposite said dripping position of said three rows and adapted each time one of said three rows occupies its said dripping position to drip a portion of said coating composition into such of said objects which are carried by the said receiving members of last said row; ejecting means arranged in said frame inside said drum opposite said ejection position of said rows, actuating means connected to said ejection means for actuating the same to eject when one of said rows occupies the said cap ejection position from said cap receiving members of last said row such of said objects which are carried by last said receiving members; for each said row a driving member rotatably mounted on said drum; first driving -means connecting said driving member and said receiving members of the corresponding one of said three rows for rotating of last said receiving members; an arm pivoted on said drum and having a pivot axis, a driving wheel rotatably mounted on said arm excentrically to said pivot axis, second driving means connecting said driving wheel and said driving member, a driving ring rotatably arranged in said frame coaxial to the axis of rotation of said drum; ring driving means connected to said driving ring for continuous rotation thereof; yielding means influencing said arm for urging the same to a position in which said driving wheel engages said driving ring; a guide member on said arm; a guide cam stationarily arranged in said frame and adapted to engage said guide member and thereby to swing said arm to an inactive position in which said driving wheel is spaced from said driving ring, said guide cam having such an extent that it engages said guide member on said arm after the corresponding one of said rows has during rotation of said drum moved away from said dripping position, but before it has reached said ejection position and remains in engagement with said guide member until the said corresponding one of said rows during further rotation of said drum has moved away from said cap receiving position, but before it has reached said dripping position.

12 5. A machine for applying 'a coating to the inner side of caps and the like dished objects which are rotated during the introduction of a liquid coating composition into said objects so that said coating compositon is bycen trifugal forces distributed over the portions to be coated of said inner surfaces of said objects; comprising in combination; a machine frame; a drum rotatably mounted in said frame; a drum driving device connected to said drum for periodical rotation thereof through an angle of not more than 120 a time between at least three stopped positions of said drum; at least three rows'of cap receiving members on said drum, each said row extending in the axial direction of said drum, each said receiving member rotatably mounted on said drum and being provided with an outwardly open dished portion for receiving one of said objects, said drum having a drum wall; each said receiving member being arranged on a hollow shaft extending through said wall, each said receiving member being provided with a central bottom opening communicating with said hollow shaft; an ejector pin slida-bly arranged in each said hollow shaft and having an inner end projecting from said hollow shaft at the inner end thereof; each of said rows taking up at one of said stopped positions of said drum a cap receiving position, at another of said stopped positions of said drum a coating composition dripping position, and at a third of said stopped drum positions of said drum a cap ejective position, said cap receiving position being the same for all said three rows, said dripping position being the same for all said three rows, and said cap ejection position being the same for all said three rows; a series of cap feeding devices stationarily arranged in said frame outside said drum opposite said cap receiving position of said rows and adapted each time one of said three rows occupies the said cap receiving position torforce one of said objectstinto each of said receiving members of last said row; a series of coating composition dripping devices stationarily arranged in said frame outside said drum opposite said dripping position of said rows and adapted each time one of said three rows 7 occupies the said dripping position to drip a portion of said coating composition into such of said objects which are carried by the said receiving members of the last said row; an ejector beam arranged in said frame inside said drum opposite to said ejection position of said rows; said beam being displaceable in its transverse direction radially relative to the drum; a moving device on said frame connected to said beam for transverse displacement thereof towards and away from the said drum wall; actuating means for actuating said moving device for displacement of said beam when one of said rows occupies the said cap ejection position towards said wall for providing engagement between said beam and said inner ends of the said ejector pins of the row occupying the said ejection position thereby pressing said ejector pins outwards through said hollow shafts .for ejection of said caps carried by the corresponding ones of said receiving members; for each said row a cap driving device arranged on said drum and adapted to rotate said receiving members of the corresponding one of said rows; rotation control means cooperating with said cap driving devices and adapted to actuate each said cap driving device before,

during and after the corresponding one of said rows occupies its said dripping position, and to inactivate each said cap driving device at least when the corresponding one of said three rows occupies its said cap receiving position and when last said row occupies its said cap ex- 8. A machine as defined in claim said frame comprising a stationary shaft extending lengthwise through said drum; said moving device comprising at least one piston device to be driving by a medium under pressure; said piston device comprising a stationary and a displaceable part, said stationary part being secured to said stationary shaft, said displaceable part being connected to said beam.

9. A machine as defined in claim 8, said drum being rotatably mounted on said stationary shaft.

10. A machine as defined in claim 5, each said ejector pin being provided at its said inner end with a bump head to cooperate with said beam.

11. A machine as defined in claim 5, each said ejector pin being provided at its outer end with an ejector disc for engagement with one of said objects carried by the corresponding receiving member.

12. A machine for applying a coating to the inner side of caps and the like dished objects which are rotated during the introduction of a liquid coating composition into said objects so that said coating composition is by centrifugal forces distributed over the portions to be coated of said inner surface of said objects; comprising in combination; a machine frame, a drum rotatably mounted in said frame; a drum driving device connected to said drum for periodical rotation thereof through an angle of not more than 120 a time between at least three stopped positions of said drum; at least three rows of cap receiving members in said drum each said row extending in the axial direction of said drum, each said receiving member being rotatably mounted on said drum and being provided with an outwardly open dished portion for receiving one of said objects; each of said rows taking up at one of said stopped positions of said drum a cap receiving position, at another of said stopped positions of said drum a coating composition dripping position, and at a third of said stopped positions of said drum a cap ejection position, said cap receiving position being the same for all said three rows, said dripping position being the same for all said three rows and said cap ejection position being the same for all said three rows; a series of cap feeding devices stationarily arranged in said frame outside said drum opposite said cap receiving position of said rows and adapted each time one of said three rows occupies the said cap receiving position to force one of said objects into each of said receiving members of last said row; a series of outlet means for said fluid coating composition stationarily arranged in said frame outside said drum opposite said dripping position of said rows, a supply line connected to each said outlet means for feeding said fluid coating composition to said outlet means; each said supply line including an electromagnetic valve provided with electric control means inserted in an electric control circuit; valve actuating means inserted in said circuit to actuate said electric control means for opening of said valve during an opening period of predetermined length each time one of said rows occupies the said dripping position so that a portion of said coating material through said outlets is dripped into such of said objects which are carried by the said receiving members of the last said row; ejection means arranged in said frame opposite said ejection position of said rows; actuating means connected to said ejection means for actuating the same to eject when one of said rows occupies the said cap ejection position from said cap receiving members of last said row such of said objects which are carried by last said receiving members; for each said row a cap driving device arranged on said drum and adapted to rotate said receiving members of the corresponding one of said rows; rotation control means cooperating with said cap driving devices and adapted to actuate each said cap driving device before, during and after the corresponding one of said rows occupies its said dripping position, and to inactivate each said cap driving device at least when the corresponding one of said three rows occupies its said cap receiving position and when last said row occupies its said cap ejection position.

13. A machine as defined in claim 12; said valve actuating means comprising a time relay determining the said predetermined length of said opening period.

14. A machine as defined in claim 13, said time relay being adjustable.

15. A machine as defined in claim 12; said valve actuating means comprising a time relay determining the said predetermined length of said opening period, said time relay having an energizing circuit; said energizing circuit including a breaker connected to a feeler movably arrangedin said frame in such a position that during said rotation of said drum it engages at least one of said receiving members when the one of said rows including last said receiving member moves into the said dripping position; last said receiving member having an outer edge engaging said feeler; said feeler being when engaging last said receiving member in an inactive position; last said receiving member having a depth less than the total height of each of said objects so that one of said objects when carried by last said receiving member extends outside said outer edge thereof; said feeler being when engaging one of said objects carried by last said receiving member moved to an active position by which said breaker is closed, so that said electromagnetic valve is opened and said fluid coating composition dripped out of the corresponding of said outlet means only when last said receiving member carries of said objects.

16. A machine as defined in claim 12, said electromagnetic valve being of the type comprising a compressible hose inserted in said supply line, a displaceable pressure member adapted to compress said hose; a spring member urging said pressure member towards a closing position in which said hose is compressed by said pressure member; an electromagnet comprising a slidable armature, said pressure member being connected to said armature; said electromagnet being adapted when energized to draw said pressure member away from said closing position for liberation of said hose.

17. A machine as defined in claim 1; said drum driving device comprising a driving shaft rotatably mounted in said frame and making one revolution for each travelling of said drum; a first actuating device for actuating said cap feeding devices each time one of said three rows occupies its said cap receiving position; a second actuation device for actuating said ejector means to eject when one of said rows occupies the said ejection position from said receiving members of last said row such said objects which are can ried by last said receiving members; and a control device connected to said driving shaft for actuating said first and said actuating device once for each revolution of said driving shaft.

References Cited UNITED STATES PATENTS 1,227,619 5/1917 Hodgson 118-320 X 2,287,356 6/1942 Newman 118319 X 2,330,880 10/1943 Gladfelter et al. 118319 X 2,390,457 1 2/1945 Pearson et al. 118318 X 2,442,179 5/1948 Shanklin et al 118-55 2,528,506 11/1950 Foye 18 2,553,590 5/1951 Joswig 18 3,046,937 7/1962 Lobersky et al. 118324 X 3,053,221 9/1962 Hefiley et al 11855 X 3,192,891 7/1965 Maehl 118314 3,202,065 8/1965 Bolcato 18 DANIEL BLUM, Primary Examiner. 

1. A MACHINE FOR APPLYING A COATING TO THE INNER SIDE OF CAPS AND THE LIKE DISHED OBJECTS WHICH ARE ROTATED DURING THE INTRODUCTION OF A LIQUID COATING COMPOSITION INTO SAID OBJECTS SO THAT SAID COATING COMPOSITION IS BY CENTRIFUGAL FORCES DISTRIBUTED OVER THE PORTIONS TO BE COATED OF SAID INNER SURFACES OF SAID OBJECTS; COMPRISING IN COMBINATION; A MACHINE FRAME; A DRUM ROTATABLY MOUNTED IN SAID FRAME; A DRUM DRIVING DEVICE CONNECTED TO SAID DRUM FOR PERIODICAL ROTATION THEREOF AN ANGLE OF NOT MORE THAN 120* A TIME BETWEEN AT LEAST THREE STOPPED POSITIONS OF SAID DRUM; AT LEAST THREE ROWS OF CAP RECEIVING MEMBERS ON SAID DRUM, EACH SAID ROW EXTENDING IN THE AXIAL DIRECTION OF SAID DRUM, EACH SAID RECEIVING MEMBER BEING ROTATABLY MOUNTED ON SAID DRUM AND BEING PROVIDED WITH AN OUTWARDLY OPEN DISHED PORTION OFOR RECEIVING ONE OF SAID OBJECTS, EACH OF SAID ROWS TAKING UP AT ONE OF SAID STOPPED POSITIONS OF SAID DRUM, A CAP RECEIVING POSITION, AT ANOTHER OF SAID STOPPED POSITIONS OF SAID DRUM A COATING COMPOSITION DRIPPING POSITION, AND AT A THIRD OF SAID STOPPED DRUM POSITIONS OF SAID DRUM A CAP EJECTION POSITIONS, SAID CAP RECEIVING POSITION BEING THE SAME FOR ALL SAID THREE ROWS, SAID DRIPPING POSITION BEING THE SAME FOR ALL SAID THREE ROWS, AND SAID CAP EJECTION POSITION BEING THE SAME FOR ALL SAID THREE ROWS; A SERIES OF CAP FEEDING DEVICES STATIONARILY ARRANGED IN SAID FRAME OUTSIDE SAID DRUM OPPOSITE SAID CAP RECEIVING POSITION OF SAID ROWS AND ADAPTED TIME ONE OF SAID THREE ROWS OCCUPIES THE SAID CAP RECEIVING POSITION TO FORCE ONE OF SAID OBJECTS INTO EACH OF SAID RECEIVING MEMBERS OF LAST SAID ROW; A SERIES OF COATING COMPOSITIONS DRIPPING DEVICES STATIONARILY ARRANGED IN SAID FRAME OUTSIDE SAID DRUM OPPOSITE SAID DRIPPING POSITION OF SAID ROWS AND ADAPTED EACH TIME ONE OF SAID THREE ROWS OCCUPIES THAT SAID DRIPPING POSITION TO DRIP A PORTION OF SAID COATING COMPOSITION INTO SUCH OF SAID OBJECTS WHICH ARE CARRIED BY THE SAID RECEIVING MEMBERS OF THE LAST SAID ROW; EJECTION MEANS ARRANGED IN SAID FRAME OPPOSITE SAID EJECTION POSITION OF SAID ROWS; ACTUATING MEANS CONNECTED TO SAID EJECTION MEANS FOR ACTUATING THE SAME TO EJECT WHEN ONE OF SAID ROWS OCCUPIES THE SAID CAP EJECTION POSITION FROM SAID CAP RECEIVING MEMBERS OF LAST SAID ROW SUCH OBJECTS WHICH ARE CARRIED BY LAST SAID RECEIVING MEMBERS; FOR EACH SAID ROW A CAP DRIVING DEVICE ARRANGED ON SAID DRUM AND ADAPTED TO ROTATE SAID RECEIVING MEMBERS OF THE CORRESPONDING ONE OF THE SAID ROWS; ROTATION CONTROL MEANS COOPERATING WITH SAID CAP DRIVIING DEVICES AND ADAPTED ACTUATE EACH SAID CAP DRIVING DEVICES BEFORE THE CORRESPONDING ONE OF SAID THREE ROWS DURING SAID PERIODICAL DRIVING OF SAID DRUM ARRIVES AT SAID DRIPPING POSITION AND SAID CAP DRIVING DEVICE TO REMAIN ACTUATED UNTIL SAID ROW HAS BEEN MOVED AWAY FROM SAID DRIPPING POSITIONS, AND TO INACTIVATE EACH SAID CAP DRIVING DEVICE BEFORE THE CORRESPONDING ONE OF SAID THREE ROWS ARRIVES TO SAID CAP EXTRACTION POSITION. 